Description
Using yeast 2-hybrid analysis, protein pull-down assays, and mutation analysis, it is showed that the first coiled-coil domain of rat Snip interacted with the N-terminal t-SNARE domain of Snap25 (600322). Biochemical studies demonstrated that Snip was tightly associated with rat brain cytoskeleton. Indirect immunofluorescence and confocal microscopy of rat PC12 pheochromocytoma cells revealed colocalization of Snip with Snap25 in the actin cytoskeleton, particularly in filopodia, lamellipodia, and neuritic extensions, including the tips. Overexpression of Snip or its Snap25-interacting domain inhibited calcium-dependent exocytosis from PC12 cells. It is concluded that SNIP is involved in regulation of neurosecretion, perhaps via its interaction with SNAP25 and the cytoskeleton